diff options
Diffstat (limited to 'drivers/media/v4l2-core/videobuf2-v4l2.c')
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-v4l2.c | 1661 |
1 files changed, 1661 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c new file mode 100644 index 000000000000..27b4b9e7c0c2 --- /dev/null +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c @@ -0,0 +1,1661 @@ +/* + * videobuf2-v4l2.c - V4L2 driver helper framework + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak <pawel@osciak.com> + * Marek Szyprowski <m.szyprowski@samsung.com> + * + * The vb2_thread implementation was based on code from videobuf-dvb.c: + * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs] + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation. + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/freezer.h> +#include <linux/kthread.h> + +#include <media/v4l2-dev.h> +#include <media/v4l2-fh.h> +#include <media/v4l2-event.h> +#include <media/v4l2-common.h> + +#include <media/videobuf2-v4l2.h> + +#include "videobuf2-internal.h" + +/* Flags that are set by the vb2 core */ +#define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \ + V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \ + V4L2_BUF_FLAG_PREPARED | \ + V4L2_BUF_FLAG_TIMESTAMP_MASK) +/* Output buffer flags that should be passed on to the driver */ +#define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \ + V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE) + +/** + * __verify_planes_array() - verify that the planes array passed in struct + * v4l2_buffer from userspace can be safely used + */ +static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + if (!V4L2_TYPE_IS_MULTIPLANAR(b->type)) + return 0; + + /* Is memory for copying plane information present? */ + if (NULL == b->m.planes) { + dprintk(1, "multi-planar buffer passed but " + "planes array not provided\n"); + return -EINVAL; + } + + if (b->length < vb->num_planes || b->length > VB2_MAX_PLANES) { + dprintk(1, "incorrect planes array length, " + "expected %d, got %d\n", vb->num_planes, b->length); + return -EINVAL; + } + + return 0; +} + +/** + * __verify_length() - Verify that the bytesused value for each plane fits in + * the plane length and that the data offset doesn't exceed the bytesused value. + */ +static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b) +{ + unsigned int length; + unsigned int bytesused; + unsigned int plane; + + if (!V4L2_TYPE_IS_OUTPUT(b->type)) + return 0; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + for (plane = 0; plane < vb->num_planes; ++plane) { + length = (b->memory == VB2_MEMORY_USERPTR || + b->memory == VB2_MEMORY_DMABUF) + ? b->m.planes[plane].length + : vb->planes[plane].length; + bytesused = b->m.planes[plane].bytesused + ? b->m.planes[plane].bytesused : length; + + if (b->m.planes[plane].bytesused > length) + return -EINVAL; + + if (b->m.planes[plane].data_offset > 0 && + b->m.planes[plane].data_offset >= bytesused) + return -EINVAL; + } + } else { + length = (b->memory == VB2_MEMORY_USERPTR) + ? b->length : vb->planes[0].length; + + if (b->bytesused > length) + return -EINVAL; + } + + return 0; +} + +static int __set_timestamp(struct vb2_buffer *vb, const void *pb) +{ + const struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + struct vb2_queue *q = vb->vb2_queue; + + if (q->is_output) { + /* + * For output buffers copy the timestamp if needed, + * and the timecode field and flag if needed. + */ + if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY) + vbuf->timestamp = b->timestamp; + vbuf->flags |= b->flags & V4L2_BUF_FLAG_TIMECODE; + if (b->flags & V4L2_BUF_FLAG_TIMECODE) + vbuf->timecode = b->timecode; + } + return 0; +}; + +static void vb2_warn_zero_bytesused(struct vb2_buffer *vb) +{ + static bool check_once; + + if (check_once) + return; + + check_once = true; + WARN_ON(1); + + pr_warn("use of bytesused == 0 is deprecated and will be removed in the future,\n"); + if (vb->vb2_queue->allow_zero_bytesused) + pr_warn("use VIDIOC_DECODER_CMD(V4L2_DEC_CMD_STOP) instead.\n"); + else + pr_warn("use the actual size instead.\n"); +} + +static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b, + const char *opname) +{ + if (b->type != q->type) { + dprintk(1, "%s: invalid buffer type\n", opname); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "%s: buffer index out of range\n", opname); + return -EINVAL; + } + + if (q->bufs[b->index] == NULL) { + /* Should never happen */ + dprintk(1, "%s: buffer is NULL\n", opname); + return -EINVAL; + } + + if (b->memory != q->memory) { + dprintk(1, "%s: invalid memory type\n", opname); + return -EINVAL; + } + + return __verify_planes_array(q->bufs[b->index], b); +} + +/** + * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be + * returned to userspace + */ +static int __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb) +{ + struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + struct vb2_queue *q = vb->vb2_queue; + unsigned int plane; + + /* Copy back data such as timestamp, flags, etc. */ + b->index = vb->index; + b->type = vb->type; + b->memory = vb->memory; + b->bytesused = 0; + + b->flags = vbuf->flags; + b->field = vbuf->field; + b->timestamp = vbuf->timestamp; + b->timecode = vbuf->timecode; + b->sequence = vbuf->sequence; + b->reserved2 = 0; + b->reserved = 0; + + if (q->is_multiplanar) { + /* + * Fill in plane-related data if userspace provided an array + * for it. The caller has already verified memory and size. + */ + b->length = vb->num_planes; + for (plane = 0; plane < vb->num_planes; ++plane) { + struct v4l2_plane *pdst = &b->m.planes[plane]; + struct vb2_plane *psrc = &vb->planes[plane]; + + pdst->bytesused = psrc->bytesused; + pdst->length = psrc->length; + if (q->memory == VB2_MEMORY_MMAP) + pdst->m.mem_offset = psrc->m.offset; + else if (q->memory == VB2_MEMORY_USERPTR) + pdst->m.userptr = psrc->m.userptr; + else if (q->memory == VB2_MEMORY_DMABUF) + pdst->m.fd = psrc->m.fd; + pdst->data_offset = psrc->data_offset; + memset(pdst->reserved, 0, sizeof(pdst->reserved)); + } + } else { + /* + * We use length and offset in v4l2_planes array even for + * single-planar buffers, but userspace does not. + */ + b->length = vb->planes[0].length; + b->bytesused = vb->planes[0].bytesused; + if (q->memory == VB2_MEMORY_MMAP) + b->m.offset = vb->planes[0].m.offset; + else if (q->memory == VB2_MEMORY_USERPTR) + b->m.userptr = vb->planes[0].m.userptr; + else if (q->memory == VB2_MEMORY_DMABUF) + b->m.fd = vb->planes[0].m.fd; + } + + /* + * Clear any buffer state related flags. + */ + b->flags &= ~V4L2_BUFFER_MASK_FLAGS; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK; + if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) != + V4L2_BUF_FLAG_TIMESTAMP_COPY) { + /* + * For non-COPY timestamps, drop timestamp source bits + * and obtain the timestamp source from the queue. + */ + b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + switch (vb->state) { + case VB2_BUF_STATE_QUEUED: + case VB2_BUF_STATE_ACTIVE: + b->flags |= V4L2_BUF_FLAG_QUEUED; + break; + case VB2_BUF_STATE_ERROR: + b->flags |= V4L2_BUF_FLAG_ERROR; + /* fall through */ + case VB2_BUF_STATE_DONE: + b->flags |= V4L2_BUF_FLAG_DONE; + break; + case VB2_BUF_STATE_PREPARED: + b->flags |= V4L2_BUF_FLAG_PREPARED; + break; + case VB2_BUF_STATE_PREPARING: + case VB2_BUF_STATE_DEQUEUED: + case VB2_BUF_STATE_REQUEUEING: + /* nothing */ + break; + } + + if (vb2_buffer_in_use(q, vb)) + b->flags |= V4L2_BUF_FLAG_MAPPED; + + return 0; +} + +/** + * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a + * v4l2_buffer by the userspace. It also verifies that struct + * v4l2_buffer has a valid number of planes. + */ +static int __fill_vb2_buffer(struct vb2_buffer *vb, + const void *pb, struct vb2_plane *planes) +{ + struct vb2_queue *q = vb->vb2_queue; + const struct v4l2_buffer *b = pb; + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); + unsigned int plane; + int ret; + + ret = __verify_length(vb, b); + if (ret < 0) { + dprintk(1, "plane parameters verification failed: %d\n", ret); + return ret; + } + if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) { + /* + * If the format's field is ALTERNATE, then the buffer's field + * should be either TOP or BOTTOM, not ALTERNATE since that + * makes no sense. The driver has to know whether the + * buffer represents a top or a bottom field in order to + * program any DMA correctly. Using ALTERNATE is wrong, since + * that just says that it is either a top or a bottom field, + * but not which of the two it is. + */ + dprintk(1, "the field is incorrectly set to ALTERNATE " + "for an output buffer\n"); + return -EINVAL; + } + vbuf->timestamp.tv_sec = 0; + vbuf->timestamp.tv_usec = 0; + vbuf->sequence = 0; + + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) { + if (b->memory == VB2_MEMORY_USERPTR) { + for (plane = 0; plane < vb->num_planes; ++plane) { + planes[plane].m.userptr = + b->m.planes[plane].m.userptr; + planes[plane].length = + b->m.planes[plane].length; + } + } + if (b->memory == VB2_MEMORY_DMABUF) { + for (plane = 0; plane < vb->num_planes; ++plane) { + planes[plane].m.fd = + b->m.planes[plane].m.fd; + planes[plane].length = + b->m.planes[plane].length; + } + } + + /* Fill in driver-provided information for OUTPUT types */ + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * Will have to go up to b->length when API starts + * accepting variable number of planes. + * + * If bytesused == 0 for the output buffer, then fall + * back to the full buffer size. In that case + * userspace clearly never bothered to set it and + * it's a safe assumption that they really meant to + * use the full plane sizes. + * + * Some drivers, e.g. old codec drivers, use bytesused == 0 + * as a way to indicate that streaming is finished. + * In that case, the driver should use the + * allow_zero_bytesused flag to keep old userspace + * applications working. + */ + for (plane = 0; plane < vb->num_planes; ++plane) { + struct vb2_plane *pdst = &planes[plane]; + struct v4l2_plane *psrc = &b->m.planes[plane]; + + if (psrc->bytesused == 0) + vb2_warn_zero_bytesused(vb); + + if (vb->vb2_queue->allow_zero_bytesused) + pdst->bytesused = psrc->bytesused; + else + pdst->bytesused = psrc->bytesused ? + psrc->bytesused : pdst->length; + pdst->data_offset = psrc->data_offset; + } + } + } else { + /* + * Single-planar buffers do not use planes array, + * so fill in relevant v4l2_buffer struct fields instead. + * In videobuf we use our internal V4l2_planes struct for + * single-planar buffers as well, for simplicity. + * + * If bytesused == 0 for the output buffer, then fall back + * to the full buffer size as that's a sensible default. + * + * Some drivers, e.g. old codec drivers, use bytesused == 0 as + * a way to indicate that streaming is finished. In that case, + * the driver should use the allow_zero_bytesused flag to keep + * old userspace applications working. + */ + if (b->memory == VB2_MEMORY_USERPTR) { + planes[0].m.userptr = b->m.userptr; + planes[0].length = b->length; + } + + if (b->memory == VB2_MEMORY_DMABUF) { + planes[0].m.fd = b->m.fd; + planes[0].length = b->length; + } + + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + if (b->bytesused == 0) + vb2_warn_zero_bytesused(vb); + + if (vb->vb2_queue->allow_zero_bytesused) + planes[0].bytesused = b->bytesused; + else + planes[0].bytesused = b->bytesused ? + b->bytesused : planes[0].length; + } else + planes[0].bytesused = 0; + + } + + /* Zero flags that the vb2 core handles */ + vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS; + if ((vb->vb2_queue->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) != + V4L2_BUF_FLAG_TIMESTAMP_COPY || !V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * Non-COPY timestamps and non-OUTPUT queues will get + * their timestamp and timestamp source flags from the + * queue. + */ + vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK; + } + + if (V4L2_TYPE_IS_OUTPUT(b->type)) { + /* + * For output buffers mask out the timecode flag: + * this will be handled later in vb2_internal_qbuf(). + * The 'field' is valid metadata for this output buffer + * and so that needs to be copied here. + */ + vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE; + vbuf->field = b->field; + } else { + /* Zero any output buffer flags as this is a capture buffer */ + vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS; + } + + return 0; +} + +static const struct vb2_buf_ops v4l2_buf_ops = { + .fill_user_buffer = __fill_v4l2_buffer, + .fill_vb2_buffer = __fill_vb2_buffer, + .set_timestamp = __set_timestamp, +}; + +/** + * vb2_querybuf() - query video buffer information + * @q: videobuf queue + * @b: buffer struct passed from userspace to vidioc_querybuf handler + * in driver + * + * Should be called from vidioc_querybuf ioctl handler in driver. + * This function will verify the passed v4l2_buffer structure and fill the + * relevant information for the userspace. + * + * The return values from this function are intended to be directly returned + * from vidioc_querybuf handler in driver. + */ +int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + struct vb2_buffer *vb; + int ret; + + if (b->type != q->type) { + dprintk(1, "wrong buffer type\n"); + return -EINVAL; + } + + if (b->index >= q->num_buffers) { + dprintk(1, "buffer index out of range\n"); + return -EINVAL; + } + vb = q->bufs[b->index]; + ret = __verify_planes_array(vb, b); + + return ret ? ret : vb2_core_querybuf(q, b->index, b); +} +EXPORT_SYMBOL(vb2_querybuf); + +/** + * vb2_reqbufs() - Wrapper for vb2_core_reqbufs() that also verifies + * the memory and type values. + * @q: videobuf2 queue + * @req: struct passed from userspace to vidioc_reqbufs handler + * in driver + */ +int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req) +{ + int ret = vb2_verify_memory_type(q, req->memory, req->type); + + return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count); +} +EXPORT_SYMBOL_GPL(vb2_reqbufs); + +/** + * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel + * @q: videobuf2 queue + * @b: buffer structure passed from userspace to vidioc_prepare_buf + * handler in driver + * + * Should be called from vidioc_prepare_buf ioctl handler of a driver. + * This function: + * 1) verifies the passed buffer, + * 2) calls buf_prepare callback in the driver (if provided), in which + * driver-specific buffer initialization can be performed, + * + * The return values from this function are intended to be directly returned + * from vidioc_prepare_buf handler in driver. + */ +int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + int ret; + + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + ret = vb2_queue_or_prepare_buf(q, b, "prepare_buf"); + + return ret ? ret : vb2_core_prepare_buf(q, b->index, b); +} +EXPORT_SYMBOL_GPL(vb2_prepare_buf); + +/** + * vb2_create_bufs() - Wrapper for vb2_core_create_bufs() that also verifies + * the memory and type values. + * @q: videobuf2 queue + * @create: creation parameters, passed from userspace to vidioc_create_bufs + * handler in driver + */ +int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) +{ + int ret = vb2_verify_memory_type(q, create->memory, + create->format.type); + + create->index = q->num_buffers; + if (create->count == 0) + return ret != -EBUSY ? ret : 0; + return ret ? ret : vb2_core_create_bufs(q, create->memory, + &create->count, &create->format); +} +EXPORT_SYMBOL_GPL(vb2_create_bufs); + +static int vb2_internal_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + int ret = vb2_queue_or_prepare_buf(q, b, "qbuf"); + + return ret ? ret : vb2_core_qbuf(q, b->index, b); +} + +/** + * vb2_qbuf() - Queue a buffer from userspace + * @q: videobuf2 queue + * @b: buffer structure passed from userspace to vidioc_qbuf handler + * in driver + * + * Should be called from vidioc_qbuf ioctl handler of a driver. + * This function: + * 1) verifies the passed buffer, + * 2) if necessary, calls buf_prepare callback in the driver (if provided), in + * which driver-specific buffer initialization can be performed, + * 3) if streaming is on, queues the buffer in driver by the means of buf_queue + * callback for processing. + * + * The return values from this function are intended to be directly returned + * from vidioc_qbuf handler in driver. + */ +int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + + return vb2_internal_qbuf(q, b); +} +EXPORT_SYMBOL_GPL(vb2_qbuf); + +static int vb2_internal_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, + bool nonblocking) +{ + int ret; + + if (b->type != q->type) { + dprintk(1, "invalid buffer type\n"); + return -EINVAL; + } + + ret = vb2_core_dqbuf(q, b, nonblocking); + + if (!ret && !q->is_output && + b->flags & V4L2_BUF_FLAG_LAST) + q->last_buffer_dequeued = true; + + return ret; +} + +/** + * vb2_dqbuf() - Dequeue a buffer to the userspace + * @q: videobuf2 queue + * @b: buffer structure passed from userspace to vidioc_dqbuf handler + * in driver + * @nonblocking: if true, this call will not sleep waiting for a buffer if no + * buffers ready for dequeuing are present. Normally the driver + * would be passing (file->f_flags & O_NONBLOCK) here + * + * Should be called from vidioc_dqbuf ioctl handler of a driver. + * This function: + * 1) verifies the passed buffer, + * 2) calls buf_finish callback in the driver (if provided), in which + * driver can perform any additional operations that may be required before + * returning the buffer to userspace, such as cache sync, + * 3) the buffer struct members are filled with relevant information for + * the userspace. + * + * The return values from this function are intended to be directly returned + * from vidioc_dqbuf handler in driver. + */ +int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_internal_dqbuf(q, b, nonblocking); +} +EXPORT_SYMBOL_GPL(vb2_dqbuf); + +/** + * vb2_streamon - start streaming + * @q: videobuf2 queue + * @type: type argument passed from userspace to vidioc_streamon handler + * + * Should be called from vidioc_streamon handler of a driver. + * This function: + * 1) verifies current state + * 2) passes any previously queued buffers to the driver and starts streaming + * + * The return values from this function are intended to be directly returned + * from vidioc_streamon handler in the driver. + */ +int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_core_streamon(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamon); + +/** + * vb2_streamoff - stop streaming + * @q: videobuf2 queue + * @type: type argument passed from userspace to vidioc_streamoff handler + * + * Should be called from vidioc_streamoff handler of a driver. + * This function: + * 1) verifies current state, + * 2) stop streaming and dequeues any queued buffers, including those previously + * passed to the driver (after waiting for the driver to finish). + * + * This call can be used for pausing playback. + * The return values from this function are intended to be directly returned + * from vidioc_streamoff handler in the driver + */ +int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type) +{ + if (vb2_fileio_is_active(q)) { + dprintk(1, "file io in progress\n"); + return -EBUSY; + } + return vb2_core_streamoff(q, type); +} +EXPORT_SYMBOL_GPL(vb2_streamoff); + +/** + * vb2_expbuf() - Export a buffer as a file descriptor + * @q: videobuf2 queue + * @eb: export buffer structure passed from userspace to vidioc_expbuf + * handler in driver + * + * The return values from this function are intended to be directly returned + * from vidioc_expbuf handler in driver. + */ +int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb) +{ + return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index, + eb->plane, eb->flags); +} +EXPORT_SYMBOL_GPL(vb2_expbuf); + +/** + * vb2_queue_init() - initialize a videobuf2 queue + * @q: videobuf2 queue; this structure should be allocated in driver + * + * The vb2_queue structure should be allocated by the driver. The driver is + * responsible of clearing it's content and setting initial values for some + * required entries before calling this function. + * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer + * to the struct vb2_queue description in include/media/videobuf2-core.h + * for more information. + */ +int vb2_queue_init(struct vb2_queue *q) +{ + /* + * Sanity check + */ + if (WARN_ON(!q) || + WARN_ON(q->timestamp_flags & + ~(V4L2_BUF_FLAG_TIMESTAMP_MASK | + V4L2_BUF_FLAG_TSTAMP_SRC_MASK))) + return -EINVAL; + + /* Warn that the driver should choose an appropriate timestamp type */ + WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN); + + /* Warn that vb2_memory should match with v4l2_memory */ + if (WARN_ON(VB2_MEMORY_MMAP != (int)V4L2_MEMORY_MMAP) + || WARN_ON(VB2_MEMORY_USERPTR != (int)V4L2_MEMORY_USERPTR) + || WARN_ON(VB2_MEMORY_DMABUF != (int)V4L2_MEMORY_DMABUF)) + return -EINVAL; + + if (q->buf_struct_size == 0) + q->buf_struct_size = sizeof(struct vb2_v4l2_buffer); + + q->buf_ops = &v4l2_buf_ops; + q->is_multiplanar = V4L2_TYPE_IS_MULTIPLANAR(q->type); + q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); + + return vb2_core_queue_init(q); +} +EXPORT_SYMBOL_GPL(vb2_queue_init); + +static int __vb2_init_fileio(struct vb2_queue *q, int read); +static int __vb2_cleanup_fileio(struct vb2_queue *q); + +/** + * vb2_queue_release() - stop streaming, release the queue and free memory + * @q: videobuf2 queue + * + * This function stops streaming and performs necessary clean ups, including + * freeing video buffer memory. The driver is responsible for freeing + * the vb2_queue structure itself. + */ +void vb2_queue_release(struct vb2_queue *q) +{ + __vb2_cleanup_fileio(q); + vb2_core_queue_release(q); +} +EXPORT_SYMBOL_GPL(vb2_queue_release); + +/** + * vb2_poll() - implements poll userspace operation + * @q: videobuf2 queue + * @file: file argument passed to the poll file operation handler + * @wait: wait argument passed to the poll file operation handler + * + * This function implements poll file operation handler for a driver. + * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will + * be informed that the file descriptor of a video device is available for + * reading. + * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor + * will be reported as available for writing. + * + * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any + * pending events. + * + * The return values from this function are intended to be directly returned + * from poll handler in driver. + */ +unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) +{ + struct video_device *vfd = video_devdata(file); + unsigned long req_events = poll_requested_events(wait); + struct vb2_buffer *vb = NULL; + unsigned int res = 0; + unsigned long flags; + + if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { + struct v4l2_fh *fh = file->private_data; + + if (v4l2_event_pending(fh)) + res = POLLPRI; + else if (req_events & POLLPRI) + poll_wait(file, &fh->wait, wait); + } + + if (!q->is_output && !(req_events & (POLLIN | POLLRDNORM))) + return res; + if (q->is_output && !(req_events & (POLLOUT | POLLWRNORM))) + return res; + + /* + * Start file I/O emulator only if streaming API has not been used yet. + */ + if (q->num_buffers == 0 && !vb2_fileio_is_active(q)) { + if (!q->is_output && (q->io_modes & VB2_READ) && + (req_events & (POLLIN | POLLRDNORM))) { + if (__vb2_init_fileio(q, 1)) + return res | POLLERR; + } + if (q->is_output && (q->io_modes & VB2_WRITE) && + (req_events & (POLLOUT | POLLWRNORM))) { + if (__vb2_init_fileio(q, 0)) + return res | POLLERR; + /* + * Write to OUTPUT queue can be done immediately. + */ + return res | POLLOUT | POLLWRNORM; + } + } + + /* + * There is nothing to wait for if the queue isn't streaming, or if the + * error flag is set. + */ + if (!vb2_is_streaming(q) || q->error) + return res | POLLERR; + /* + * For compatibility with vb1: if QBUF hasn't been called yet, then + * return POLLERR as well. This only affects capture queues, output + * queues will always initialize waiting_for_buffers to false. + */ + if (q->waiting_for_buffers) + return res | POLLERR; + + /* + * For output streams you can write as long as there are fewer buffers + * queued than there are buffers available. + */ + if (q->is_output && q->queued_count < q->num_buffers) + return res | POLLOUT | POLLWRNORM; + + if (list_empty(&q->done_list)) { + /* + * If the last buffer was dequeued from a capture queue, + * return immediately. DQBUF will return -EPIPE. + */ + if (q->last_buffer_dequeued) + return res | POLLIN | POLLRDNORM; + + poll_wait(file, &q->done_wq, wait); + } + + /* + * Take first buffer available for dequeuing. + */ + spin_lock_irqsave(&q->done_lock, flags); + if (!list_empty(&q->done_list)) + vb = list_first_entry(&q->done_list, struct vb2_buffer, + done_entry); + spin_unlock_irqrestore(&q->done_lock, flags); + + if (vb && (vb->state == VB2_BUF_STATE_DONE + || vb->state == VB2_BUF_STATE_ERROR)) { + return (q->is_output) ? + res | POLLOUT | POLLWRNORM : + res | POLLIN | POLLRDNORM; + } + return res; +} +EXPORT_SYMBOL_GPL(vb2_poll); + +/** + * struct vb2_fileio_buf - buffer context used by file io emulator + * + * vb2 provides a compatibility layer and emulator of file io (read and + * write) calls on top of streaming API. This structure is used for + * tracking context related to the buffers. + */ +struct vb2_fileio_buf { + void *vaddr; + unsigned int size; + unsigned int pos; + unsigned int queued:1; +}; + +/** + * struct vb2_fileio_data - queue context used by file io emulator + * + * @cur_index: the index of the buffer currently being read from or + * written to. If equal to q->num_buffers then a new buffer + * must be dequeued. + * @initial_index: in the read() case all buffers are queued up immediately + * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles + * buffers. However, in the write() case no buffers are initially + * queued, instead whenever a buffer is full it is queued up by + * __vb2_perform_fileio(). Only once all available buffers have + * been queued up will __vb2_perform_fileio() start to dequeue + * buffers. This means that initially __vb2_perform_fileio() + * needs to know what buffer index to use when it is queuing up + * the buffers for the first time. That initial index is stored + * in this field. Once it is equal to q->num_buffers all + * available buffers have been queued and __vb2_perform_fileio() + * should start the normal dequeue/queue cycle. + * + * vb2 provides a compatibility layer and emulator of file io (read and + * write) calls on top of streaming API. For proper operation it required + * this structure to save the driver state between each call of the read + * or write function. + */ +struct vb2_fileio_data { + struct v4l2_requestbuffers req; + struct v4l2_plane p; + struct v4l2_buffer b; + struct vb2_fileio_buf bufs[VB2_MAX_FRAME]; + unsigned int cur_index; + unsigned int initial_index; + unsigned int q_count; + unsigned int dq_count; + unsigned read_once:1; + unsigned write_immediately:1; +}; + +/** + * __vb2_init_fileio() - initialize file io emulator + * @q: videobuf2 queue + * @read: mode selector (1 means read, 0 means write) + */ +static int __vb2_init_fileio(struct vb2_queue *q, int read) +{ + struct vb2_fileio_data *fileio; + int i, ret; + unsigned int count = 0; + + /* + * Sanity check + */ + if (WARN_ON((read && !(q->io_modes & VB2_READ)) || + (!read && !(q->io_modes & VB2_WRITE)))) + return -EINVAL; + + /* + * Check if device supports mapping buffers to kernel virtual space. + */ + if (!q->mem_ops->vaddr) + return -EBUSY; + + /* + * Check if streaming api has not been already activated. + */ + if (q->streaming || q->num_buffers > 0) + return -EBUSY; + + /* + * Start with count 1, driver can increase it in queue_setup() + */ + count = 1; + + dprintk(3, "setting up file io: mode %s, count %d, read_once %d, write_immediately %d\n", + (read) ? "read" : "write", count, q->fileio_read_once, + q->fileio_write_immediately); + + fileio = kzalloc(sizeof(struct vb2_fileio_data), GFP_KERNEL); + if (fileio == NULL) + return -ENOMEM; + + fileio->read_once = q->fileio_read_once; + fileio->write_immediately = q->fileio_write_immediately; + + /* + * Request buffers and use MMAP type to force driver + * to allocate buffers by itself. + */ + fileio->req.count = count; + fileio->req.memory = VB2_MEMORY_MMAP; + fileio->req.type = q->type; + q->fileio = fileio; + ret = vb2_core_reqbufs(q, fileio->req.memory, &fileio->req.count); + if (ret) + goto err_kfree; + + /* + * Check if plane_count is correct + * (multiplane buffers are not supported). + */ + if (q->bufs[0]->num_planes != 1) { + ret = -EBUSY; + goto err_reqbufs; + } + + /* + * Get kernel address of each buffer. + */ + for (i = 0; i < q->num_buffers; i++) { + fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0); + if (fileio->bufs[i].vaddr == NULL) { + ret = -EINVAL; + goto err_reqbufs; + } + fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0); + } + + /* + * Read mode requires pre queuing of all buffers. + */ + if (read) { + bool is_multiplanar = q->is_multiplanar; + + /* + * Queue all buffers. + */ + for (i = 0; i < q->num_buffers; i++) { + struct v4l2_buffer *b = &fileio->b; + + memset(b, 0, sizeof(*b)); + b->type = q->type; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + b->m.planes = &fileio->p; + b->length = 1; + } + b->memory = q->memory; + b->index = i; + ret = vb2_internal_qbuf(q, b); + if (ret) + goto err_reqbufs; + fileio->bufs[i].queued = 1; + } + /* + * All buffers have been queued, so mark that by setting + * initial_index to q->num_buffers + */ + fileio->initial_index = q->num_buffers; + fileio->cur_index = q->num_buffers; + } + + /* + * Start streaming. + */ + ret = vb2_core_streamon(q, q->type); + if (ret) + goto err_reqbufs; + + return ret; + +err_reqbufs: + fileio->req.count = 0; + vb2_core_reqbufs(q, fileio->req.memory, &fileio->req.count); + +err_kfree: + q->fileio = NULL; + kfree(fileio); + return ret; +} + +/** + * __vb2_cleanup_fileio() - free resourced used by file io emulator + * @q: videobuf2 queue + */ +static int __vb2_cleanup_fileio(struct vb2_queue *q) +{ + struct vb2_fileio_data *fileio = q->fileio; + + if (fileio) { + vb2_core_streamoff(q, q->type); + q->fileio = NULL; + fileio->req.count = 0; + vb2_reqbufs(q, &fileio->req); + kfree(fileio); + dprintk(3, "file io emulator closed\n"); + } + return 0; +} + +/** + * __vb2_perform_fileio() - perform a single file io (read or write) operation + * @q: videobuf2 queue + * @data: pointed to target userspace buffer + * @count: number of bytes to read or write + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + * @read: access mode selector (1 means read, 0 means write) + */ +static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblock, int read) +{ + struct vb2_fileio_data *fileio; + struct vb2_fileio_buf *buf; + bool is_multiplanar = q->is_multiplanar; + /* + * When using write() to write data to an output video node the vb2 core + * should set timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody + * else is able to provide this information with the write() operation. + */ + bool set_timestamp = !read && + (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY; + int ret, index; + + dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n", + read ? "read" : "write", (long)*ppos, count, + nonblock ? "non" : ""); + + if (!data) + return -EINVAL; + + /* + * Initialize emulator on first call. + */ + if (!vb2_fileio_is_active(q)) { + ret = __vb2_init_fileio(q, read); + dprintk(3, "vb2_init_fileio result: %d\n", ret); + if (ret) + return ret; + } + fileio = q->fileio; + + /* + * Check if we need to dequeue the buffer. + */ + index = fileio->cur_index; + if (index >= q->num_buffers) { + /* + * Call vb2_dqbuf to get buffer back. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + fileio->b.m.planes = &fileio->p; + fileio->b.length = 1; + } + ret = vb2_internal_dqbuf(q, &fileio->b, nonblock); + dprintk(5, "vb2_dqbuf result: %d\n", ret); + if (ret) + return ret; + fileio->dq_count += 1; + + fileio->cur_index = index = fileio->b.index; + buf = &fileio->bufs[index]; + + /* + * Get number of bytes filled by the driver + */ + buf->pos = 0; + buf->queued = 0; + buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0) + : vb2_plane_size(q->bufs[index], 0); + /* Compensate for data_offset on read in the multiplanar case. */ + if (is_multiplanar && read && + fileio->b.m.planes[0].data_offset < buf->size) { + buf->pos = fileio->b.m.planes[0].data_offset; + buf->size -= buf->pos; + } + } else { + buf = &fileio->bufs[index]; + } + + /* + * Limit count on last few bytes of the buffer. + */ + if (buf->pos + count > buf->size) { + count = buf->size - buf->pos; + dprintk(5, "reducing read count: %zd\n", count); + } + + /* + * Transfer data to userspace. + */ + dprintk(3, "copying %zd bytes - buffer %d, offset %u\n", + count, index, buf->pos); + if (read) + ret = copy_to_user(data, buf->vaddr + buf->pos, count); + else + ret = copy_from_user(buf->vaddr + buf->pos, data, count); + if (ret) { + dprintk(3, "error copying data\n"); + return -EFAULT; + } + + /* + * Update counters. + */ + buf->pos += count; + *ppos += count; + + /* + * Queue next buffer if required. + */ + if (buf->pos == buf->size || (!read && fileio->write_immediately)) { + /* + * Check if this is the last buffer to read. + */ + if (read && fileio->read_once && fileio->dq_count == 1) { + dprintk(3, "read limit reached\n"); + return __vb2_cleanup_fileio(q); + } + + /* + * Call vb2_qbuf and give buffer to the driver. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + fileio->b.index = index; + fileio->b.bytesused = buf->pos; + if (is_multiplanar) { + memset(&fileio->p, 0, sizeof(fileio->p)); + fileio->p.bytesused = buf->pos; + fileio->b.m.planes = &fileio->p; + fileio->b.length = 1; + } + if (set_timestamp) + v4l2_get_timestamp(&fileio->b.timestamp); + ret = vb2_internal_qbuf(q, &fileio->b); + dprintk(5, "vb2_dbuf result: %d\n", ret); + if (ret) + return ret; + + /* + * Buffer has been queued, update the status + */ + buf->pos = 0; + buf->queued = 1; + buf->size = vb2_plane_size(q->bufs[index], 0); + fileio->q_count += 1; + /* + * If we are queuing up buffers for the first time, then + * increase initial_index by one. + */ + if (fileio->initial_index < q->num_buffers) + fileio->initial_index++; + /* + * The next buffer to use is either a buffer that's going to be + * queued for the first time (initial_index < q->num_buffers) + * or it is equal to q->num_buffers, meaning that the next + * time we need to dequeue a buffer since we've now queued up + * all the 'first time' buffers. + */ + fileio->cur_index = fileio->initial_index; + } + + /* + * Return proper number of bytes processed. + */ + if (ret == 0) + ret = count; + return ret; +} + +size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, + loff_t *ppos, int nonblocking) +{ + return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1); +} +EXPORT_SYMBOL_GPL(vb2_read); + +size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, + loff_t *ppos, int nonblocking) +{ + return __vb2_perform_fileio(q, (char __user *) data, count, + ppos, nonblocking, 0); +} +EXPORT_SYMBOL_GPL(vb2_write); + +struct vb2_threadio_data { + struct task_struct *thread; + vb2_thread_fnc fnc; + void *priv; + bool stop; +}; + +static int vb2_thread(void *data) +{ + struct vb2_queue *q = data; + struct vb2_threadio_data *threadio = q->threadio; + struct vb2_fileio_data *fileio = q->fileio; + bool set_timestamp = false; + int prequeue = 0; + int index = 0; + int ret = 0; + + if (q->is_output) { + prequeue = q->num_buffers; + set_timestamp = + (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == + V4L2_BUF_FLAG_TIMESTAMP_COPY; + } + + set_freezable(); + + for (;;) { + struct vb2_buffer *vb; + + /* + * Call vb2_dqbuf to get buffer back. + */ + memset(&fileio->b, 0, sizeof(fileio->b)); + fileio->b.type = q->type; + fileio->b.memory = q->memory; + if (prequeue) { + fileio->b.index = index++; + prequeue--; + } else { + call_void_qop(q, wait_finish, q); + if (!threadio->stop) + ret = vb2_internal_dqbuf(q, &fileio->b, 0); + call_void_qop(q, wait_prepare, q); + dprintk(5, "file io: vb2_dqbuf result: %d\n", ret); + } + if (ret || threadio->stop) + break; + try_to_freeze(); + + vb = q->bufs[fileio->b.index]; + if (!(fileio->b.flags & V4L2_BUF_FLAG_ERROR)) + if (threadio->fnc(vb, threadio->priv)) + break; + call_void_qop(q, wait_finish, q); + if (set_timestamp) + v4l2_get_timestamp(&fileio->b.timestamp); + if (!threadio->stop) + ret = vb2_internal_qbuf(q, &fileio->b); + call_void_qop(q, wait_prepare, q); + if (ret || threadio->stop) + break; + } + + /* Hmm, linux becomes *very* unhappy without this ... */ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + } + return 0; +} + +/* + * This function should not be used for anything else but the videobuf2-dvb + * support. If you think you have another good use-case for this, then please + * contact the linux-media mailinglist first. + */ +int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, + const char *thread_name) +{ + struct vb2_threadio_data *threadio; + int ret = 0; + + if (q->threadio) + return -EBUSY; + if (vb2_is_busy(q)) + return -EBUSY; + if (WARN_ON(q->fileio)) + return -EBUSY; + + threadio = kzalloc(sizeof(*threadio), GFP_KERNEL); + if (threadio == NULL) + return -ENOMEM; + threadio->fnc = fnc; + threadio->priv = priv; + + ret = __vb2_init_fileio(q, !q->is_output); + dprintk(3, "file io: vb2_init_fileio result: %d\n", ret); + if (ret) + goto nomem; + q->threadio = threadio; + threadio->thread = kthread_run(vb2_thread, q, "vb2-%s", thread_name); + if (IS_ERR(threadio->thread)) { + ret = PTR_ERR(threadio->thread); + threadio->thread = NULL; + goto nothread; + } + return 0; + +nothread: + __vb2_cleanup_fileio(q); +nomem: + kfree(threadio); + return ret; +} +EXPORT_SYMBOL_GPL(vb2_thread_start); + +int vb2_thread_stop(struct vb2_queue *q) +{ + struct vb2_threadio_data *threadio = q->threadio; + int err; + + if (threadio == NULL) + return 0; + threadio->stop = true; + /* Wake up all pending sleeps in the thread */ + vb2_queue_error(q); + err = kthread_stop(threadio->thread); + __vb2_cleanup_fileio(q); + threadio->thread = NULL; + kfree(threadio); + q->threadio = NULL; + return err; +} +EXPORT_SYMBOL_GPL(vb2_thread_stop); + +/* + * The following functions are not part of the vb2 core API, but are helper + * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations + * and struct vb2_ops. + * They contain boilerplate code that most if not all drivers have to do + * and so they simplify the driver code. + */ + +/* The queue is busy if there is a owner and you are not that owner. */ +static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file) +{ + return vdev->queue->owner && vdev->queue->owner != file->private_data; +} + +/* vb2 ioctl helpers */ + +int vb2_ioctl_reqbufs(struct file *file, void *priv, + struct v4l2_requestbuffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type); + + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + res = vb2_core_reqbufs(vdev->queue, p->memory, &p->count); + /* If count == 0, then the owner has released all buffers and he + is no longer owner of the queue. Otherwise we have a new owner. */ + if (res == 0) + vdev->queue->owner = p->count ? file->private_data : NULL; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs); + +int vb2_ioctl_create_bufs(struct file *file, void *priv, + struct v4l2_create_buffers *p) +{ + struct video_device *vdev = video_devdata(file); + int res = vb2_verify_memory_type(vdev->queue, p->memory, + p->format.type); + + p->index = vdev->queue->num_buffers; + /* + * If count == 0, then just check if memory and type are valid. + * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0. + */ + if (p->count == 0) + return res != -EBUSY ? res : 0; + if (res) + return res; + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + res = vb2_core_create_bufs(vdev->queue, p->memory, &p->count, + &p->format); + if (res == 0) + vdev->queue->owner = file->private_data; + return res; +} +EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs); + +int vb2_ioctl_prepare_buf(struct file *file, void *priv, + struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_prepare_buf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf); + +int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + /* No need to call vb2_queue_is_busy(), anyone can query buffers. */ + return vb2_querybuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf); + +int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_qbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf); + +int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf); + +int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamon(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamon); + +int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_streamoff(vdev->queue, i); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff); + +int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) +{ + struct video_device *vdev = video_devdata(file); + + if (vb2_queue_is_busy(vdev, file)) + return -EBUSY; + return vb2_expbuf(vdev->queue, p); +} +EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf); + +/* v4l2_file_operations helpers */ + +int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct video_device *vdev = video_devdata(file); + + return vb2_mmap(vdev->queue, vma); +} +EXPORT_SYMBOL_GPL(vb2_fop_mmap); + +int _vb2_fop_release(struct file *file, struct mutex *lock) +{ + struct video_device *vdev = video_devdata(file); + + if (lock) + mutex_lock(lock); + if (file->private_data == vdev->queue->owner) { + vb2_queue_release(vdev->queue); + vdev->queue->owner = NULL; + } + if (lock) + mutex_unlock(lock); + return v4l2_fh_release(file); +} +EXPORT_SYMBOL_GPL(_vb2_fop_release); + +int vb2_fop_release(struct file *file) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + + return _vb2_fop_release(file, lock); +} +EXPORT_SYMBOL_GPL(vb2_fop_release); + +ssize_t vb2_fop_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (!(vdev->queue->io_modes & VB2_WRITE)) + return -EINVAL; + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_write(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_write); + +ssize_t vb2_fop_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct video_device *vdev = video_devdata(file); + struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock; + int err = -EBUSY; + + if (!(vdev->queue->io_modes & VB2_READ)) + return -EINVAL; + if (lock && mutex_lock_interruptible(lock)) + return -ERESTARTSYS; + if (vb2_queue_is_busy(vdev, file)) + goto exit; + err = vb2_read(vdev->queue, buf, count, ppos, + file->f_flags & O_NONBLOCK); + if (vdev->queue->fileio) + vdev->queue->owner = file->private_data; +exit: + if (lock) + mutex_unlock(lock); + return err; +} +EXPORT_SYMBOL_GPL(vb2_fop_read); + +unsigned int vb2_fop_poll(struct file *file, poll_table *wait) +{ + struct video_device *vdev = video_devdata(file); + struct vb2_queue *q = vdev->queue; + struct mutex *lock = q->lock ? q->lock : vdev->lock; + unsigned res; + void *fileio; + + /* + * If this helper doesn't know how to lock, then you shouldn't be using + * it but you should write your own. + */ + WARN_ON(!lock); + + if (lock && mutex_lock_interruptible(lock)) + return POLLERR; + + fileio = q->fileio; + + res = vb2_poll(vdev->queue, file, wait); + + /* If fileio was started, then we have a new queue owner. */ + if (!fileio && q->fileio) + q->owner = file->private_data; + if (lock) + mutex_unlock(lock); + return res; +} +EXPORT_SYMBOL_GPL(vb2_fop_poll); + +#ifndef CONFIG_MMU +unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct video_device *vdev = video_devdata(file); + + return vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags); +} +EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area); +#endif + +/* vb2_ops helpers. Only use if vq->lock is non-NULL. */ + +void vb2_ops_wait_prepare(struct vb2_queue *vq) +{ + mutex_unlock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare); + +void vb2_ops_wait_finish(struct vb2_queue *vq) +{ + mutex_lock(vq->lock); +} +EXPORT_SYMBOL_GPL(vb2_ops_wait_finish); + +MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2"); +MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski"); +MODULE_LICENSE("GPL"); |